Sari Harrar

Seventeen outbreaks, 222 cases. That doesn’t sound like much. But when the Centers for Disease Control and Prevention released new measles statistics last week, the report sounded a warning. Compared to the year 2000 – when the CDC says there was a record low of just 86 cases – the numbers mark a 15-year-high for this sometimes-deadly viral infection.

Measles, once almost a childhood rite of passage, was nearly wiped out thanks to high vaccination rates. Now it’s returning. Numbers paint the picture:

In 2011, kids and teens caught the most measles – 61 percent of cases. Just 39 percent were in people over age 19.

27 cases were in babies younger than age 1 — too young to receive the first dose of the mumps, measles and rubella (MMR) vaccine that cuts measles risk by 90 percent.

Nobody died from measles last year in the U.S., thank goodness. (The virus kills about 164,000 people worldwide each year.) In the U.S., 70 people were hospitalized, 15 became dehydrated (which can be especially dangerous in little kids and in older people) and 12 developed pneumonia.

141 cases –two-thirds of the total — were in kids and young adults who hadn’t received the MMR vaccine, but were eligible for it.

Measles is back for two reasons: More Americans are being exposed to measles virus from overseas sources – because they’re traveling (Europe had 30,000 cases last year) or come in contact with someone who was exposed to it outside the U.S. According to USA Today, three babies less than a year old (too young for vaccination) were infected in a California doctor's waiting room when a 7-year-old who had caught measles in Switzerland came in to be seen.

And as more parents refuse immunizations, infection is more likely. Fears about links between vaccines and autism lead to a drop in immunizations in Europe, where measles had been under control in the 1990s. Last year, 8 people in Europe died from measles and its complications.

“Maintenance of high MMR vaccination coverage is essential to prevent measles outbreaks and sustain measles elimination in the United States,” the CDC says. “Despite the relatively small number of reported cases in the United States, the public and the health-care providers must remain vigilant. A drop in MMR vaccination coverage in a community can increase the risk for large, sustained measles outbreaks, as experienced recently in Canada and France.”

Measles virus spreads through the air – an infected kid coughs, sneezes or even breathes out the virus and any unvaccinated kid who is exposed is likely to also become infected. It’s that contagious. One worry is that measles will once again become endemic in the U.S. – meaning it’s always present, always getting passed around. The CDC says measles was no longer endemic by 2000, but that could change.

Another concern: The upcoming Olympics in London this summer, as well as the Euro 2012 soccer cup in Poland and Ukraine – both of which draw tens of thousands of American spectators. "Disease knows no borders," Rebecca Martin, director of the CDC's Global Immunization Division, told USA Today in March. "We are concerned about Americans coming back from the Olympics this summer and unknowingly infecting others."

The government recommends all kids get two MMR vaccine shots: One between the ages of 12 and 15 months, a second between ages 4 and 6. Infants who will be traveling overseas should get at least one shot if they’re between 6 and 11 months old, and kids 12 months or older should get both shots (separated by at least 28 days). And while many adults already have immunity to measles, you may need the vaccine if you were born after 1957 or haven’t yet been vaccinated and are a woman of childbearing age, a student at college or any post high-school institution, a healthcare worker or an international traveler. You’ll find more details at here.